<div>
    If you want to always run this project on a specific node/slave, just specify its name.
    This works well when you have a small number of nodes.

    <p>
    As the size of the cluster grows, it becomes useful not to tie projects to specific slaves,
    as it hurts resource utilization when slaves may come and go. For such situation, assign labels
    to slaves to classify their capabilities and characteristics, and specify a boolean expression
    over those labels to decide where to run.

    <h3>Valid Operators</h3>
    <p>
    The following operators are supported, in the order of precedence.
    <dl>
        <dt>(expr)</dt>
        <dd>parenthesis</dd>

        <dt>!expr</dt>
        <dd>negation</dd>
    
        <dt>expr&amp;&amp;expr</dt>
        <dd>
            and
        </dd>

        <dt>expr||expr</dt>
        <dd>
            or
        </dd>

        <dt>a -> b</dt>
        <dd>
            "implies" operator. Equivalent to <tt>!a|b</tt>.
            For example, <tt>windows->x64</tt> could be thought of as "if run on a Windows slave,
            that slave must be 64bit." It still allows Hudson to run this build on linux.
        </dd>

        <dt>a &lt;-> b</dt>
        <dd>
            "if and only if" operator. Equivalent to <tt>a&amp;&amp;b || !a&amp;&amp;!b</tt>.
            For example, <tt>windows->sfbay</tt> could be thought of as "if run on a Windows slave,
            that slave must be in the SF bay area, but if not on Windows, it must not be in the bay area."
        </dd>
    </dl>
    <p>
    All operators are left-associative (i.e., a->b->c &lt;-> (a->b)->c )
    An expression can contain whitespace for better readability, and it'll be ignored.

    <p>
    Label names or slave names can be quoted if they contain unsafe characters. For example,
    <tt>"hudson-solaris (Solaris)" || "Windows 2008"</tt>
</div>